1. Field of the Invention
This invention relates to a magneto-optical recording medium such as a magneto-optical disk which is used for a large-capacity information file or the like. This invention particularly relates to an improvement of a magneto-optical recording layer of the magneto-optical recording medium.
2. Description of the Prior Art
Among optical recording media having various advantages, for example, the advantage that they can record information at a high density, have a large capacity, and need not be contacted with a head, magneto-optical recording media have attracted attention from the viewpoint of easy erasing and rerecording.
The magneto-optical recording medium is composed of a magnetic material as a recording medium, and records information based on changes in magnetization of the magnetic material. For example, an amorphous alloy composed of a combination of a rare earth metal (RE) such as Gd, Tb or Dy with a transition metal such as Fe, Co or Ni is used as the magnetic material. The magnetic material is used in a layer form as a recording layer.
A problem with the aforesaid magneto-optical recording medium is how to improve bit stability for the purpose of improving the C/N ratio in the course of magnetic recording and reproducing. It has heretofore been known that, in order to improve the bit stability, the coercive force should be increased by increasing the magnetic anisotropy of the magnetic material in the recording layer in the vertical direction.
Therefore, research has heretofore been undertaken to increase the coercive force of the magnetic material in the recording layer.